1. Field of Invention
The present invention is generally in the field of electronic communications. More particularly, the present invention is in the field of wireless electronic communications.
2. Background
In wireless communications, such as Bluetooth wireless communications, one electronic device (a paging device) typically initiates communication by paging another electronic device (a paged device) to establish a connection between the two devices. For example, a paging device can begin by transmitting a modulated signal including an ID packet to a paged device. The paged device can detect the modulated signal and can transmit a response signal to the paging device on a new frequency associated with the frequency on which the modulated signal was transmitted. The paged device can then wait for the paging device to send a response, such as a frequency hop synchronization (FHS) packet. The paging device can then send the response, e.g., the FHS packet, and can then wait for another response from the paged device.
The paging device, however, might often unintentionally transmit false modulated signals on frequencies other than the frequency on which the intended modulated signal is transmitted. The false modulated signals, for example, are typically created in the transmitter of the paging device by spurious signals that might undesirably become modulated during the modulation of the desired signals. Such false modulated signals may be inadvertently detected by the paged device, causing substantial delays in the paging process. Moreover, under strong signal conditions (e.g., when the desired signal is very strong), the false modulated signal can be large enough for the receiver of the paged device to detect the false modulated signal.
For example, when a paged device detects a false modulated signal, the paged device demodulates the false modulated signal and transmits a response signal to the paging device on a new frequency associated with the frequency on which the false modulated signal was transmitted. However, since the paging device is configured to listen to a response signal from the paged device on a frequency associated with the intended modulated signal, the paging device will be unable to properly reply to the response signal sent by the paged device. Furthermore, while the paged device is engaged in attempting to “close the loop” initiated by a false page, the paged device might miss true pages intended for the paged device. As such, the detection of false modulated signals by a paged device can substantially delay the paging and communication processes and can ultimately cause the paging process to fail.